Homeowner FAQ

General FAQs

How much insulation do I legally need for my [attic, wall, etc.] if I live in [insert city or province here]?

The amount of insulation your home or building needs depends on where you live. Contact your local building code official for definitive code requirements. Note that municipalities have different approaches to renovation work, and there may be a legal requirement that applies.

My contractor is suggesting [insert insulation type], but I feel differently. What type of insulation do I need?

Vapour retarders are typically recommended for the interior side (i.e., the “warm in winter” side) of above-ground framed walls in your home, such as bedrooms, bathrooms, garages, and attics. A vapour retarder is not required for basement walls, walls made of materials that can’t be damaged by moisture or freezing, or any parts of walls that are below ground. Note that many Canadian codes use the terms “vapour barrier” and “vapour retarder” interchangeably. The latter is technically more accurate.

The fiberglass, rock wool, and slag wool products used in the construction industry today are safe for use when recommended work practices are followed. For detailed information on the health and safety of mineral fiber, please contact the insulation manufacturer and visit our Health and Safety section of the website for homes, residential buildings, non-residential buildings, and mechanical systems.

What is the difference between an R-value, RSI-value, and a U-thermal transmittance?

Thermal resistance requirements in Canada are under the jurisdiction of the 13 provinces and territories, with a few chartered municipalities that adopt and enforce their own requirements (e.g., the Vancouver Building By-Law 9419 ). For this reason, there is a lot of variation in the requirements across Canada. Some jurisdictions express minimum thermal resistance codes using nominal values, others using effective values.

The use of nominal values is easier for the insulation industry, since the product packaging is marked with these values and they directly correlate with the amount of insulation required in a building assembly (e.g., above ground walls, roofs).

However there is a move away from nominal to effective requirements in codes, with effective values representing the total thermal resistance of the whole assembly, not only insulation. Therefore it is important that the insulation industry and its supply channels learn how to calculate the nominal insulation needed to meet those code requirements that are expressed in effective thermal resistance. There is no single conversion factor, since the effective values account for each feature of the assembly contributing to thermal resistance, and features vary from building structure to building structure.

Homeowner FAQs

Which type of insulation do I need?

The type of insulation you need depends on where it will be installed, what R-values are required, and your budget. Where you live also affects which insulation you choose. For example, a home in Toronto will have different minimum R-value requirements than one in Yellowknife. Check with your local building codes.

What is blown-in or loose-fill insulation?

Blown-in or loose-fill mineral fiber insulation is typically used in unfinished attics, nonconforming spaces, and hard-to-reach areas, such as corners, edges, and around framing. This type of insulation usually requires a blowing machine for installation.

What is mineral wool?

In Canada, this term is used to cover any mineral fiber insulation: glass, rock, and slag material fibers. (See CAN ULC S 773 for more information.) Specifically designed to deliver robust thermal insulation and/or sound dampening, exceptional fire resistance and superior temperature control, it is most commonly installed in wood-stud cavities of interior and exterior walls, basements, ceilings, floors, and crawl spaces.

How can I reduce moisture in my home?

The most important step is to ensure that your home has a continuous air barrier. Wall cavities typically have an air barrier on one side (continuous for the whole of the building’s exterior structure, and vapour retarders on the other (usually warm) side. An air conditioner or de-humidifier programmed to keep the correct moisture level in the air will handle the rest. Remember that air that is too dry is not recommended for healthy living.

How often does insulation need to be replaced?

Mineral fibre is designed for longevity and permanence, and, with the exception of unusual circumstances (i.e., floods, leaks, fires, or poor maintenance), it maintains its insulating (both thermal and acoustic) properties and rarely needs to be replaced. When our mineral fiber products are installed and properly maintained, they do not compress, settle, or erode over time, retaining their thermal and acoustic performances.

Is mineral fiber fire resistant?

Both fiberglass and rock or slag wool are naturally non-combustible. For additional information on fire safety of various insulation products, please refer to our product comparison page.